C/CF/Cu复合材料界面和抗拉强度研究

Tensile strength and interface of C/CF/Cu composite material

采用树脂碳化方法制备了碳/碳纤维(C/CF)先驱丝,用压力浸渗凝固成型方法制备了碳/碳纤维/铜(C/CF/Cu)复合材料,借助抗拉强度测试及扫描电镜下复合材料界面和相组成物分布观察,探讨了C、CF和Cu三组元复合界面特性以及碳纤维丝类型和C/CF先驱丝体积分数对C/CF/Cu复合材料抗拉强度的影响。结果表明,C/CF/Cu复合材料的微观界面是碳纤维单丝-树脂碳化碳-铜双复合界面,此界面属于无化学反应的弱复合界面,铜对C/CF先驱丝的机械锁紧力是提高界面强度和复合材料强度的关键因素。当凝固成型压力为28.5MPa时,1k碳纤维丝的C/CF先驱丝体积分数为25%和3k碳纤维丝的C/CF先驱丝体积分数为44.7%的复合材料的抗拉强度达到较高值,分别为595MPa和587MPa,均为纯铜抗拉强度的3倍以上。3k丝制成的一次C/CF先驱丝内碳纤维丝的数量较多,影响复合材料的界面强度,而选用1k碳纤维丝比较有利。

Carbon/carbon fibers （C/CF） perform bars were prepared by resin carbonation. Carbon/carbon fibers/copper （C/CF/Cu） composite material were prepared by squeeze easting. The composite interfaee of C, CF and Cu in the eomposite material and the effeets of C/CF volume percentage and CF type on the tensile strength of C/CF/Cu eomposite material were investigated by observing and analyzing the morphology of composite interface and constituent distribution using SEM and tensile test. The results show that the composite interface is carbon fiber-resin carbonated carbon and resin carbonated earbon-Cu in C/CF/Cu composite material, respectively. The interface is weak composite interface without ehemistry reaetion. The meehanieal binding force of Cu and C/CF obviously affeets the interfaee strength and tensile strength of C/CF/Cu composite material. When volume percentage of C/CF perform bars made of lk and 3k earbon fiber is 25% and 44.7%, the tensile strength of C/ CF/Cu eomposite material is higher and reaehes up to 595 MPa and 587 MPa,respeetively,whieh is equivalent to more than three times of that of pure copper cast with 28.5 MPa squeeze pressure. Higher volume percentage of carbon fibers in C/CF perform bars made of 3k carbon fiber affects interfaee strength of C/CF/Cu composite material, but lk earbon fiber is more benefieial to that.